• The Journal of Advanced Prosthodontics
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• v.3 no.4
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• pp.196-203
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• 2011

PURPOSE. This study evaluated marginal fit of glass infiltrated alumina cores fabricated using two techniques and their marginal stability after firing cycles of veneering porcelain. MATERIALS AND METHODS. Fifteen standardized all-ceramic crowns were fabricated on a metal die using each technique: slip cast technique of VITA In-Ceram sprint Alumina (Group A as control) and plastic foil matrix technique of Turkom-Cera fused alumina core system (Group B). Copings were compared between groups and within groups at coping stage and after firing each layer of veneering porcelain. A device was used to standardize seating of copings on the metal die and positioning of the specimens under the microscope after each stage of fabrication. The specimens were not cemented and marginal gap was measured using an image analyzing software (Imagepro Express) on the photographs captured under an optical microscope. Two tailed unpaired 't test' was used to compare marginal gaps in two groups and one way ANOVA was used to analyze marginal distortion within each group at 95% confidence interval. RESULTS. The marginal gap was smaller at the coping stage in group B ($60+30{\mu}M$) than group A ($81+21{\mu}M$) with statistical significance. After firing of veneering porcelain the difference was insignificant. At the final stage, both groups exhibited lower mean marginal gaps than at the initial coping stage with the difference of $11.75{\mu}M$ for group A and $11.94{\mu}M$ for group B, but it was statistically insignificant due to high value of standard deviation. CONCLUSION. Within the limitations of this study, it was concluded that both techniques produced copings with comparable and acceptable marginal fit and marginal stability on firing veneering porcelain.

• The Journal of Advanced Prosthodontics
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• v.10 no.3
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• pp.197-204
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• 2018

PURPOSE. To determine the extent of treatment traces, the roughness depth, and the quantity of titanium nitride (TiN) removed from the surface of CAD/CAM abutments after treatment with various instruments. MATERIALS AND METHODS. Twelve TiN coated CAD/CAM abutments were investigated for an in vitro study. In the test group (9), each abutment surface was subjected twice (150 g vs. 200 g pressure) to standardized treatment in a simulated prophylaxis measure with the following instruments: acrylic scaler, titanium curette, and ultrasonic scaler with steel tip. Three abutments were used as control group. Average surface roughness (Sa) and developed interfacial area ratio (Sdr) of treated and untreated surfaces were measured with a profilometer. The extent of treatment traces were analyzed by scanning electron microscopy. RESULTS. Manipulation with ultrasonic scalers resulted in a significant increase of average surface roughness (Sa, P<.05) and developed interfacial area ratio (Sdr, P<.018). Variable contact pressure did not yield any statistically significant difference on Sa-values for all instruments (P=.8). Ultrasonic treatment resulted in pronounced surface traces and partially detachment of the TiN coating. While titanium curettes caused predominantly moderate treatment traces, no traces or detectable substance removal has been determined after manipulation with acrylic curettes. CONCLUSION. Inappropriate instruments during regular plaque control may have an adverse effect on the integrity of the TiN coating of CAD/CAM abutments. To prevent defects and an increased surface roughness at the transmucosal zone of TiN abutments, only acrylic scaling instruments can be recommended for regular maintenance care.

• Journal of Technologic Dentistry
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• v.31 no.3
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• pp.27-34
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• 2009

This study compared and analyzed changes to the mechanical characteristics to nonprecious metal alloy for porcelain fused to metal crowns when it's repetitively used without the addition of new alloy. Metal samples were made with the Verabond V nonprecious metal alloy. Those samples to measure tensile and yield strength were made in the standardized design(ISO 22674), those to measure bond strength in the $25mm{\times}3mm{\times}0.5mm$ format, and those to measure hardness in the $10mm{\times}10mm{\times}1mm$ format. A ceramic to measure bond strength was made at the center of the metal sample in the length of $8{\ss}{\AE}$ by using Noritaker Super Porcelain EX-3. Ten samples were prepared for one, three and five repetitions of casting each. The test results were as follows: 1. The more casting was repeated, the more significantly tensile strength dropped. 2. The more casting was repeated, the more significantly yield strength dropped. 3. Repetitive casting didn't cause significant changes to bond strength. 4. The Vickers hardness significantly fell with increasing repetitions of casting. There were no changes to bond strength observed with the increasing number of repeating casting. But tensile strength, yield strength, and Vickers hardness decreased. Those results indicate that repeated casting can affect durability and that careful attention should be paid by avoiding repetitive use or excessive increase of uses when no new alloy is added.

• Convergence Security Journal
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• v.14 no.7
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• pp.85-90
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• 2014

Cloud computing originated simply to request and execute the desired operation from the network of clouds. It means that an IT resource that provides a service using the Internet technology. It is getting the most attention in today's IT trends. In cloud computing networks, devices and data centers which are composed of the server, storage and application are connected over network. That is, data of computers in different physical locations are integrated using the virtualization technology to provide a service. Therefore cloud computing system is a key information resource, standardized methods and assessment system are required. In this paper, we aims to derive the parameters and information for research of technical standards stability evaluation method associated with various cloud computing equipment.

• The Journal of the Korea Contents Association
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• v.11 no.9
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• pp.372-383
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• 2011

Our study was carried out to develop the severity-adjustment model for length of stay in hospital for percutaneous coronary interventions so that we would analysis the factors on the variation in length of stay(LOS). The subjects were 1,011 percutaneous coronary interventions inpatients of the Korean National Hospital Discharge In-depth Injury Survey 2004-2006 data. The data were analyzed using t-test and ANOVA and the severity-adjustment model was developed using data mining technique. After yielding the standardized value of the difference between crude and expected length of stay, we analysed the variation of length of stay for percutaneous coronary interventions. There was variation of LOS in regional differences, size of sickbed and insurance type. The variation of length of stay controlling the case mix or severity of illness can be explained the factors of provider. This supply factors in LOS variations should be more studied for individual practice style or patient management practices and healthcare resources or environment. We expect that the severity-adjustment model using administrative databases should be more adapted in other diseases in practical.

• Korean journal of food and cookery science
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• v.16 no.6
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• pp.584-592
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• 2000

Standard recipes of various Korean soups for cook/chill system were developed to provide foodservice managers in kindergarten with more effective management system. Three kinds of soup, Miyuck-gook (Korean sea mustard soup), Soup of beef and radish and Chige of beef and soybean paste (Korean thick soup made of beef and soybean paste) were selected as menu items in this study, and the standard recipes for these soups were developed through sensory evaluation, and microbiological analyses were performed to assure the quality of soup. The microbial counts of the soups which were chilled at 0-3$^{\circ}C$ and stored for 10 days in refrigerator were as follows: Aerobic bacteria were not detected in Miyuck-gook; however, those in Soup of beef and radish were 0.00-1.32${\pm}$0.28 log CFU/g and those in Chige of beef and soybean paste were 3.36${\pm}$0.10- 4.67${\pm}$0.08 log CFU/g. Coliform bacteria were not detected in any soups. All the items of sensory evaluation showed no significant differences between the first and third day of storage, except the flavor, tenderness, chewiness, feeling after swallowing of Soup of Beef and Radish and color of Chige of Beef and Soybean Paste. Overall acceptability scores of chilled stored foods in the first and third day were 6.40:t0.83 and 6.07 :to.46 in Miyuck-gook, 6.93 ${\pm}$0.80 and 6.27${\pm}$1.16 in Soup of beef and radish, and 6.40${\pm}$1.40 and 6.07${\pm}$1.44 in Chige of beef and soybean paste, respectively.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.9
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• pp.4025-4029
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• 2015

Background: Gastrointestinal tract cancers are among the most common cancers in Iran and comprise approximately 38% of all the reported cases of cancer. This study aimed to describe the epidemiology and to investigate spatial clustering of common cancers of the gastrointestinal tract across the counties of Iran using full Bayesian smoothing and Moran I Index statistics. Materials and Methods: The data of the national registry cancer were used in this study. Besides, indirect standardized rates were calculated for 371 counties of Iranand smoothed using Winbug 1.4 software with a full Bayesian method. Global Moran I and local Moran I were also used to investigate clustering. Results: According to the results, 75,644 new cases of cancer were nationally registered in Iran among which 18,019 cases (23.8%) were esophagus, gastric, colorectal, and liver cancers. The results of Global Moran's I test were 0.60 (P=0.001), 0.47 (P=0.001), 0.29 (P=0.001), and 0.40 (P=0.001) for esophagus, gastric, colorectal, and liver cancers, respectively. This shows clustering of the four studied cancers in Iran at the national level. Conclusions: High level clustering of the cases was seen in northern, northwestern, western, and northeastern areas for esophagus, gastric, and colorectal cancers. Considering liver cancer, high clustering was observed in some counties in central, northeastern, and southern areas.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.15
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• pp.6561-6568
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• 2015

Background: Smokeless tobacco (SLT) has long been realized as an important component of the fight for global tobacco control. It still remains a major problem in countries like India, Bangladesh and Nepal. The objective of this study was to estimate the trends of SLT use in three countries of the SEARO WHO office. Materials and Methods: We used data from national surveys in three countries (Bangladesh, India and Nepal) to estimate trends in prevalence of current SLT use. All available nationally representative data sources were used. Estimates were weighted, age standardized and given along with 95% confidence intervals. Significance of linear trend in prevalence over time was tested using the Cochrane-Armitage test for trend. A p value of less than 0.05 was considered statistically significant. Results: We identified three surveys for Bangladesh, three for India and four for Nepal that met the selection criteria (such as Demographic and Health Surveys, WHO-STEPwise approach to Surveillance and Global Adult Tobacco Surveys). A significantly increasing trend was noticed in the prevalence of current SLT use among Bangladeshi men (20.2% to 23%, p=0.03). In India, a similar significantly increasing trend was seen among men (27.1% to 33.4%, p<0.001) and women (10.1% to 15.7%, p<0.001). In Nepal, there was a no significant trend among both men (39.1% to 31.6%, p=0.11) and women (5.6% to 4.7%, p=0.49). Conclusions: In the study countries SLT use has remained at alarmingly high levels. Usage trends do not show any signs of decline in spite of control efforts. Tobacco control measures should focus more on controlling SLT use.

• Journal of the Korea Society of Computer and Information
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• v.25 no.11
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• pp.147-155
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• 2020

System support software is one of the software that makes up ship combat management system and has the characteristics of being mounted in the combat management systems of all ships but with little functional change. However, despite these characteristics, software modifications due to equipment, etc. are inevitable in the application of new ships. Modification of software causes software reliability testing which is a key factor in increasing development costs. In this paper, the structure of the existing system support software was analyzed to identify and supplement the code change factors, and the system support standardization architecture was designed. The feature model elicited common and variable elements of system support software, and applied white-box reuse to improve software design. In addition, the results of comparing existing system support software with the new architecture in terms of development elements and time to perform reliability test were presented to verify the effectiveness of the new one.

• Journal of the Korean Society of Clothing and Textiles
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• v.33 no.11
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• pp.1683-1695
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• 2009

This study analyzes the production process of eight domestic companies that manufacture scuba diving suits for men with an emphasis on the level of consumer satisfaction in scuba diving suits purchases. One hundred fifty questionnaires were distributed and a total of 140 usable data were coded for further statistical analysis that includes descriptive statistics (frequency and ${\chi}^2$ test) through SPSSWIN 17.0. The results show that a majority of the domestic scuba diving suit companies were either small, manufactured products under original equipment manufacturer (OEM) brands, or were involved in the import business. Many of these companies have developed a local sizing system derived from a company database of customer sizing. As a result, different companies have different sizes that lead to confusion and complication among consumers in selecting the correct size for scuba diving suits. The results indicate that most high-priced diving suits are made of imported fabrics because they had superior quality, fitness, and thickness compared to domestic brands. The degree of consumer satisfaction with scuba diving suits was found to be low in comfort, stuffiness, and activity. Respondents indicated that they felt a little tightness in circumstances such as bust, wrist, and thigh in measurements of circumstances. On the other hand, the respondents showed a high degree of satisfaction with body fitness in scuba diving suits. Further research will clarify a standardized sizing system and develop patterns suitable for Korean men's scuba diving suit body sizes.